package com.atguigu.guliguli.common.xss;

import com.atguigu.guliguli.common.utils.RRException;
import org.apache.commons.lang.StringUtils;


/**
 * SQL过滤
 *
 * @author: yezi
 * @date: 2021/11/27 09:25
 **/
public class SQLFilter {
    /**
     * SQL注入过滤
     *
     * @param str 待验证的字符串
     */
    public static String sqlInject(String str) {
        if (StringUtils.isBlank(str)) {
            return null;
        }
//        去掉'|"|;|\字符
        str = StringUtils.replace(str, "'", "");
        str = StringUtils.replace(str, "'\"", "");
        str = StringUtils.replace(str, ";", "");
        str = StringUtils.replace(str, "\\", "");
//        转换成小写
        str = str.toLowerCase();
//        非法字符
        String[] keywords = {"master", "truncate", "insert", "select", "delete", "update", "declare", "alter", "drop"};
//    判断是否包含非法字符
        for (String keyword : keywords) {
            if (str.indexOf(keyword) != -1) {
                throw new RRException("包含非法字符");
            }
        }
        return str;
    }
}